The present invention relates to the processing of pulp in a pulp mill, including the steps of breaking down and bleaching the pulp with chemicals, and washing the chemicals from the pulp after the breaking down and the bleaching steps. More particularly, the invention relates to a shower pipe for conveying a liquid wash to a pulp mat as a vacuum drum draws the mat out of a pulp slurry containing pulp and the breaking-down or bleaching chemicals, and an improved set of nozzles and lips coupled to the shower pipe for distributing the liquid wash to the pulp mat to wash out the chemicals.